Organic light emitting diodes (OLEDs) are polycrystalline semiconductor devices, are used in backlight units to obtain high brightness light emission at low voltage, and are expected to be used in thin flat displays. However, organic light emitting diodes have problems of vulnerability to moisture, delamination at an interface between a metal layer and an organic electroluminescent (EL) layer under influence of moisture, high resistance due to oxidation of metal, and deterioration in luminous characteristics and reduction in brightness resulting from degradation of organic materials due to moisture.
To solve these problems, a method of encapsulating organic light emitting diodes using a curable composition is developed. Examples of a typical encapsulation method include a method in which an organic light emitting diode is molded from acrylic resins and a method in which a moisture absorbent material is added to an encapsulation resin for an organic light emitting diode to protect the organic light emitting diode from moisture, and the like.